I recently attempted to follow an online video via automatically generated "Closed Captioning." It was utter gibberish.
Auto-caption is so vastly a joke that "youtube auto caption fail" is a drop-down search suggestion.
I recommend that any site (like YouTube) that imposes "auto-captioning" make it easy for content producers to edit/correct the transcript. The site should alert the content producer to the importance of taking this step, and provide extensive how-to documentation.
People who rely on assistive technology should somehow be informed, whether "Closed Captioning" was produced with human oversight or was automatically generated.